The engine immobiliser system is designed to prevent the vehicle from being stolen. This system uses a transponder key ecu that stores the key codes of authorized ignition keys. If an attempt is made to start the engine using an unauthorized key, the ecu sends a signal to the ecm to prohibit fuel delivery and ignition, effectively disabling the engine.

The transponder key coil receives this signal, the transponder key amplifier amplifies it, and then the signal is transmitted to the ecu. The ecu matches the key's id code with the vehicle's id code, which was previously registered in the ecu and then communicates the results to the ecm using sfi communication.
Engine immobiliser system
How to proceed with troubleshootingRemoval
Disconnect cable from negative battery
terminal
Caution:
Wait at least 90 seconds after disconnecting the
cable from the negative (-) battery terminal to
prevent airbag and seat belt pretensioner activation.
Remove no. 1 Engine under cover
Remove front fender apron rh
Remove radia ...
Back door
The back door can be locked/unlocked and opened/closed by
the following procedures.
Locking and unlocking the back door
Door lock switch
Entry function (if equipped)
Wireless remote control
Opening/closing the back door from inside the vehicle (vehicles
with a power back door)
Press a ...
Removal (2006/01- )
Disconnect cable from negative battery
terminal
Caution:
Wait at least 90 seconds after disconnecting the
cable from the negative (-) battery terminal to
prevent airbag and seat belt pretensioner activation.
Remove front door scuff plate lh
Using a screwdriver, detach the 10 cla ...